Connectivity, i.e. the establishment of a connection or communication path between two end points in a communications network is a fundamental task in network management. A corresponding capability is provided by a connection management system. In traditional telephone service networks, connection management involves defining a user/network interface (UNI) and a network/network interface (NNI). Current standards for connectivity services on B-ISDN networks basically amount to extensions of the UNI and NNI standards.
In the 1960s, at the time when the UNI and NNI standards were introduced, it was rightly recognized that customer premises equipment (CPE) had a low level of "intelligence" in comparison with the switching equipment, and that the user was interested mainly in manipulating the service at its end points. Today these assumptions are no longer valid, as the CPE often is at least as intelligent as the switch controllers.
The ability of the connection management system to create and deploy network services rapidly will be a key factor for future service providers to succeed. As the high-speed switching and communications infrastructure is improved, and as bandwidth becomes a commodity, product differentiation increasingly may depend on the level of sophistication, degree of flexibility and speed of deployment of network services.
Recent proposals for providing connectivity service are presented in TINA-C, Service Architecture Version 2.0, Document No. TB.sub.-- MDC.012.sub.-- 2.0.sub.-- 94, March 1995 and by A. A. Lazar et al., "Realizing a Foundation for Programmability of ATM Networks with the Binding Architecture", IEEE Journal of Selected Areas in Communications, Special Issue on Distributed Multimedia Systems, Vol. 14, No. 7, September 1996, pp. 1214-1247. According to these proposals, controllers run on general-purpose distributed computing platforms and interact through local or remote invocations. This permits signaling activities to be formulated in high-level terms of operation instead of low-level mechanisms.